Why Power Banks Typically Can't, or should not be used to Charge Laptops
Power banks are usually designed to charge smaller, peripheral devices such as smartphones, headphones, and microphones. These devices normally require a relatively low power input, typically ranging between 5W and 18W, which is within the output capabilities of most standard power banks. A typical power bank rated at 10000 mAh (milliamp-hours) is more than sufficient to charge a smartphone or similar low-power device one or more times.
These are the type of power banks we usually provide, usually to power or charge a Microphone or similar peripheral during lectures etc, at no point should anything larger being charged being a possibility have been suggested to you/any student.
In contrast, laptops require a lot more power to charge and use effectively. The average power requirement for a laptop falls between 30W and 100W or sometimes more, depending on the hardware specifications and components. Most standard power banks, including the one Study Tech stocks, don't support this level of output.
Another important factor is port compatibility. Laptops use specific charging connectors or require USB-C ports with Power Delivery (PD) support, which can deliver higher voltage and current. If a power bank lacks these ports or does not support USB-PD at sufficient wattages, it will not be able to charge the laptop even if the power bank is connected.
Unless specifically designed for high-output charging and equipped with the right ports, most standard power banks aren't capable of charging a laptop.
A laptop will also need a USB port that supports power delivery.
Most standard entry level DSA awarded laptops will not have power delivery (PD) over USB, for example the hP G( or G10/255 laptops, or ASUS smaller form factor laptops.
Where a power bank can charge a laptop, the charging time of a laptop with a power bank can vary significantly based on the power bank's capacity and the laptop's power consumption. A 20,000mAh power bank might take 2-3 hours to fully charge a laptop with a 50W charger, while a smaller 10,000mAh power bank might take 4-6 hours, especially if using a lower-wattage charger.
Power Bank Capacity:
Larger power banks with higher mAh (milliampere-hour) ratings will take longer to charge and can provide more power to the laptop.
Laptop Power Consumption:
Laptops can draw anywhere from 30 to 70 watts, with gaming/higher spec laptops using more.
Charger Power:
The power output of the charger used to charge the power bank (e.g., 5V/1A, 9V/2A, or higher) will affect charging time.
Laptop Charging Compatibility:
Some laptops are not compatible with power banks and might not charge at all, while others may only charge at a trickle rate if the power output is too low, or exhaust the power bank within seconds/minutes.
Laptop: A standard laptop with a 50W charger and a 60Wh battery.
Power Bank: A 10,000mAh power bank.
Charging Time: Approximately 4-6 hours with a fast charger, if compatible (9V/2A or higher), or 9-13 hours with a standard charger (5V/1A).
In either scenario, the power bank will likely loose charge long before the laptop reaches full charge, and will potentially not even supply power enough for the laptop to be used while charging.
Important Considerations, if you do decide against our advice to charge a laptop with a power bank:
Most laptops will not charge via a power bank, even where they do, battery life is likely to be significantly shortened by using a now standard voltage/amperage/wattage for the laptop the power bank will deliver. Tolerances on laptops are not usually as broad as phones/smaller devices.
Always check the charging time and power input requirements for the power bank itself.
Ensure you're using a charging capable/non data only cable cable to connect the power bank to the laptop.
Monitor the charging process and disconnect when/if the laptop or power bank get hot, or as soon as the laptop is fully charged.